Fair Value of Financial Instruments - Net Change in Unrealized Gains or Losses on Investments for Which Level 3 Inputs were Used in Determining Fair Value (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Net Unrealized Gain (Loss)			$ 151,902		$ 61,325
Level 3
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Net Unrealized Gain (Loss)	$ 57,893	$ 26,032	92,422	$ 40,665
Level 3 | First-lien Debt Investments
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Net Unrealized Gain (Loss)	47,862	25,415	74,550	39,379
Level 3 | Second-lien Debt Investments
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Net Unrealized Gain (Loss)	2,630		4,990
Level 3 | Mezzanine Debt Investments
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Net Unrealized Gain (Loss)	258	$ 617	2,570	$ 1,286
Level 3 | Equity and Other Investments
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Net Unrealized Gain (Loss)	$ 7,143		$ 10,312